State Regulators Propose Lowering Arsenic Limit In Public Drinking Water By Half

State regulators want to cut their limit on arsenic in drinking water in half – and their research shows the change could save lives.

A bill in the legislature last year suggested the Department of Environmental Services sharply lower its limit from the Environmental Protection Agency’s default 10 parts per billion to 4 parts per trillion.

But DES told lawmakers that might be infeasible, and suggested looking into a more moderate reduction instead, such as from 10 ppb to 5 ppb.

The roughly 40 percent of New Hampshire residents who use private wells would not be required to follow the lower standard. But the UNH researchers say in their study they hope a change in state law would spur more voluntary treatment.

Advocates for drinking water protection are lauding the proposal, which will now go to the legislature for review.

CORRECTION: An earlier version of this article incorrectly stated that DES had initially felt a 5 part-per-billion standard was infeasible. In fact, the agency worried an earlier legislative proposal of 4 parts per trillion would be infeasible, and suggested looking into a limit like 5 ppb instead.

An earlier version of this story also incorrectly stated that 1 part per billion was like a drop of ink in a bathtub; in fact, it is akin to a drop of ink inside an oil tanker truck.

Drinking water from private wells in northern New England may increase the risk of bladder cancer, according to a new study from the National Cancer Institute, Dartmouth and the state health departments in New Hampshire, Maine and Vermont.

At a house in Stoddard, a Cushing and Sons truck mounted rig pounds a drill bit into bedrock 90 feet below.

“What we’re hearing now is a pneumatic hammer,” says Bart Cushing, who together with his brother runs this family owned well-drilling business, “That’s a flat-based bit with carbide buttons. And it’s literally pounding the rock.”

These artesian groundwater wells are the norm these days: something on the order of 95 percent of new wells are drilled into the bedrock.